1. Field
The present disclosure pertains to the field of electronic components. More particularly, the present disclosure pertains to selecting the ratio of an internal clock to another clock such as an external clock that is provided to an electronic component.
2. Description of Related Art
Integrated circuits and other electronic components are generally designed to operate within certain parameters. One important parameter usually specified for an electronic component is a maximum operating frequency. Typically, manufacturers can only ensure the component performs specified operations reliably as long as the user operates the component at or below the maximum operating frequency. Thus, manufacturers of electronic components would like to ensure that their parts are operated at or below the maximum operating frequency.
Unfortunately, there is a significant faction of computer users that engages in “over-clocking” of components such as processors. Over-clocking involves providing the component with a clock signal having a higher frequency than the component is designed to use. Typically, this external clock is multiplied by a predetermined multiplier to provide one or more higher frequency clocks for internal operations of the component. Alternatively, over-clocking may be accomplished in some cases by altering the predetermined multiplier so that internal operations of the component are performed at a higher multiple of the frequency of the external clock than originally intended.
Some processors allow the clock multiplier to be set by adjusting motherboard connections, software, or firmware. Other processors have their clock multipliers programmed during manufacturing by blowing out fuses, so that the clock multiplier may not be tampered with by unauthorized persons. Thus, in prior art schemes, the clock multiplier is fixed and is not adjusted or tested based on the frequency of the clock provided to the component.
An over-clocked component performs operations more rapidly and thus the user is “rewarded” with better performance. The downside of over-clocking is that logic malfunctions are more likely, and the part may be damaged or destroyed (e.g., due to overheating). Since manufacturers often conservatively specify maximum operating conditions, however, slightly over-clocked parts may operate fairly well despite the over-clocking.
Thus, over-clocking is fairly popular. Unfortunately, such over-clocking reduces the market for high-end or faster parts because over-clockers purchase lower speed parts and over-clock them to achieve the desired performance level. The sale of the lower speed parts is typically significantly less lucrative for component manufacturers.
A more nefarious problem is the combination of remarking and over-clocking. Some components illegally have their labeling altered to indicate that they are capable of operating at a higher speed. These remarked products may then be resold at a higher price because of the better performance associated with the higher frequency operation. Often, faster parts command significant premiums over their slower brethren, making remarking and over-clocking a lucrative (albeit illegal) endeavor. Moreover, remarking and over-clocking are difficult problems to address since both may be hard to detect and may occur in jurisdictions where enforcement of appropriate laws is difficult.